One of the major problems in the making of plastics is the pollution caused from the pigments used to color the plastics. When powder pigment is used it often gets into the air causing air pollution. Also these powder pigments contain heavy metal and when the dusts settles on the floor and is swept or washed down the drain or when hoppers are clean or washed and the pigment runs down the drain, heavy metals in the pigment pollute the sewage system. Further, pigment is expensive; thus the loss of this pigment is costly.
The main problem that causes this dust is when the mixer that mixes the plastic with the pigment dumps the plastic and pigment mixture into an open hopper, a great amount of the pigment is released into the air from the dumping process. This causes major problems. The first is the amount of pigment that is lost during this process cannot be calculated. Therefore, the color of the final batch cannot be adequately determined. Thus, when the color of the plastic is important the whole batch may be lost because too much of the pigment was disburse into the air during the dumping process. Secondly, this dust that is released into the air causes air pollution within the plant and raises medical and workman compensation claims of the workers in the plant. Thirdly, the cleaning up of the pigments after they have settled causes other problems. If the pigments are washed down the drain since pigments contain heavy metals, they cause water pollution. They also, because of their heavy metal content cause land fill pollution if they are disposed of in bulk. Fourthly, the loss pigment means loss money for plastics company.
To counteract this problem the plastic industrial has placed large vacuum hoses near the hopper during the pouring from the mixer. These large vacuum hoses suck up some powder. However, this powder still has to be disposed of and due to the heavy metal content of the pigments there are problems with disposal of the powder. Also, this powder that is vacuumed is lost and thus means lost of money. On the average size hopper and an average load there is approximately six dollars lost pigments per hopper.
Therefore, it is an objective of this invention to eliminate the pigment escaping into the air during the dumping process. Further, it is the objective of this invention to cut down on the amount of waste pigment so that it does not cause air pollution within a plant. Further objective of this invention to contain the powder so that it does not cause water or landfill pollution. It is also an objective of this invention to have an economical method that can control the powder and save the company's money from lost pigment.
The features of this invention are a liner or a sleeve that attaches to the mixer and attaches to or fills the hopper in such a way that when the pigment is dumped none of the pigment escape into the air but is contained by the liner. The liner's in operation costs approximately 1/3 of the cost of the lost pigment.